问题 单项选择题

某家店准备打折出售一批滞销的电脑,经核算,如果按正价打九折销售,每台还可盈利305元,如果打八折,就要亏损175元。那么这种电脑的进货价是( )元。

A.4800
B.4625
C.4015
D.3940

答案

参考答案:C

解析: 这种电脑打九折和打八折的差价是305+175=480(元),那么正价为480÷(90%-80%)=4800(元),进货价为4800×90%-305=4015(元)。故本题答案为C。

阅读理解

The Kingdome in Seattle was destroyed on March 26,2000.It was taken down to make room for a new stadium.The blast(爆破)from the failing building caused the earth to shake as if an earthquake had happened.

Scientists placed more than 200 earthquake recorders in the earth to measure the movement.They found which parts of the

city shook the most.This information helped them know which parts of the city would be damaged in a real earthquake at an early time.

A real earthquake happened on February 28, 2001 in Seattle.The Nisqually earthquake was 6.8 on the Richter scale(里氏6.8级).It damaged the same parts of Seattle that scientists had predicted from the pulling down of the Kingdome.It was a plate quake.It started deep in the earth, 37 miles below the surface on the Juan de Fuca Plate.Sometimes,huge plates under the earth cause earthquakes when the plates move against each other suddenly.

Scientists have learned that deep earthquakes have very few aftershocks(余震).The Nisqually earthquake had only 4 ones.Another earthquake in California that was close to the surface had over 120 aftershocks.Scientists do not know why the deep earthquakes have fewer aftershocks.

Scientists plan to blast in the ground near Seattle with the purpose of testing the plate.The shockwaves from the blast will jump off the plate and give them all idea of where the plate is and how it is moving.This will give them more information in case another real earthquake hits the area.

56.Why were the scientists interested in the pulling down of the Seattle Kingdome?

A.To predict what might happen in a real earthquake.

B.To see which areas near the Kingdome would shake the hardest.

C.To measure the movement of the Earth with earthquake recorders.

D.All of the above.

57.What will happen after a deep earthquake according to the scientists?

A.There will be little damage.       

B.There will be many aftershocks.

C.There will be very few aftershocks. 

D.The Richter scale of the quakes will be 6.8 or more.

58.According to the passage,      have the most aftershocks.

A.deep earthquakes        B.shockwave earthquakes

C.earthquakes close to the surface    D.earthquakes more than 6.8 Richter scale

59.By studying the blast in the ground near Seattle, scientists hope to        

A.destroy the Kingdome

B.learn where the plate is and how it is moving

C.find out how many plates there are in the ground there

D.know which places are likely to have the most damage            

单项选择题